RU194294U1 - Device for diagnosing an internal combustion engine - Google Patents

Abstract

The inventive utility model relates to tests of internal combustion engines, diagnostic tests of reciprocating engines G01M 15/04 and allows, by measuring the speed of movement of the engine flywheel and the reference point on the camshaft position sensor, to test the 16-cylinder V-shaped locomotive engine. A useful model is that the diagnosis of an internal combustion engine is performed using a speed sensor installed in the window of the flywheel housing the movement of the flywheel and the camshaft position sensor associated with the electronic data acquisition unit, while the camshaft position sensor is located in the valve cover of one of the cylinders of the internal combustion engine.

Description

Utility Model Description

The inventive utility model relates to tests of internal combustion engines, diagnostic tests of reciprocating engines G01M 15/04, and allows you to diagnose an internal combustion engine using a flywheel speed sensor installed in the window of the flywheel housing and an engine camshaft position sensor associated with the electronic collection unit data, characterized in that the camshaft position sensor is located in the valve cover of one of the engine cylinders in morning combustion.

A device is known according to Patent RU 2390745 (C2) “A method for providing high-precision data on crankshaft revolutions and position for multi-cylinder control systems and diagnostics of the engine and device for this purpose”. A device for implementing the method comprises an induction speed sensor, a constant component calculation unit, a comparator, a phase sensor (crankshaft position sensor), a galvanic isolation unit, and a microcontroller having two inputs and two outputs.

The device according to the patent - prototype works as follows:

The initial signal is obtained at the calibration stage, while the speed of the engine working without load during one cycle is stored and the constant component of this signal is calculated. Each tooth edge gives one measurement point. All deviations from the constant component are taken as systematic errors at this speed;

The measured signal is obtained at the measurement stage, while the engine is loaded at the same speed, the speed signal is recorded during one cycle, the constant component is calculated, and the systematic error obtained during calibration is subtracted from the calibration points, clearing the speed signal from it. If the measurement speed differs from the speed at which the calibration was carried out, then the systematic error is multiplied by the speed ratio.

The original signal from the induction speed sensor is added to the measured signal of the DC component calculation unit and is fed to the input of the comparator. The introduction of a constant component into this signal is necessary in order for the comparator to have unipolar power. The comparator has a hysteresis of 0.15 V, which increases its noise immunity. The output of the comparator is connected to the first input of the microcontroller, which implements a program for recording the signal of the induction speed sensor at the calibration stage, calculates the systematic error and subtracts it from the signal of the induction speed sensor at the measurement stage. From the first output of the microcontroller, the signal of the induction speed sensor, cleaned of systematic error, is fed to the input of the speed control system, which can significantly improve the quality of regulation, and, consequently, improve the economic and environmental characteristics of the engines. The phase sensor (crankshaft position sensor) can be a piezoelectric sensor mounted on the high pressure pipe of one of the engine nozzles.

In the case of a gasoline engine, it can be a special sensor built into the high-voltage wire of the spark plug. The signal of the phase sensor (crankshaft position sensor) is fed to the input of the galvanic isolation unit, which is necessary to isolate the useful signal from electrical noise from the side of the engine housing and its electrical systems. From the output of the galvanic isolation unit, the phase signal is fed to the second input of the microcontroller. The microcontroller generates a diagnostic signal of the engine speed with a phase mark on the position of the crankshaft and outputs it to the second output for use in the Diagnostic Device. This allows you to accurately determine the cylinder (or group of cylinders) in which any malfunction may occur.

The disadvantage of this device is that the very process of comparing engine operation without load, with work under load, is erroneous due to different volumes of fuel consumed at the same number of revolutions of the crankshaft.

This drawback does not allow the use of a device selected as a prototype for diagnosing the operation of an internal combustion engine of a diesel locomotive.

The objective of the claimed utility model is the use of the inventive device in the diagnosis of a 16-cylinder diesel engine. The inventive device operates as follows:

The essence of the utility model is illustrated by drawings.

FIG. 1. - a sequence diagram of the mutual arrangement of the nodes of the claimed device;

The design of this device is shown schematically in FIG. one.

During operation of the engine, the flywheel with teeth 1 also rotates. The initial signal from the flywheel speed measuring sensor 2, which measures the instantaneous flywheel speed, is input to the electronic data acquisition unit 3. A signal from the position sensor is input to the second input of the electronic data acquisition unit 3 the camshaft of the engine 4. The electronic data collection unit transmits an array of collected data over the data line 5.

A significant improvement in the quality of diagnostics of 16-cylinder engines of diesel locomotives, and consequently, an improvement in the economic and environmental characteristics of engines is achieved by the fact that, to increase the reliability of the diagnosis of the fuel system, in the inventive device, the reference is made depending on the position of the camshaft of the engine, namely, from the beginning the movement of the pusher of the exhaust valve of one of the engine cylinders.

As an example of a specific implementation of the claimed device, we consider a device for diagnosing the condition of an engine of a locomotive.

A flywheel with teeth, and a sensor for measuring the speed of movement of the teeth of the flywheel, are already installed on the locomotive, they are used to manually rotate the crankshaft with a worm gear during engine repair work, and to calculate the total speed of rotation of the crankshaft of the engine during engine operation.

FIG. 2. - Camshaft position sensor, installed next to the exhaust cam follower, top view.

The number 6 indicates the lever for opening the valves swinging on its axis. The number 7 indicates the position sensor of this lever, used as a sensor of the position of the camshaft of the engine. Before starting the diagnosis, it is necessary to replace the usual valve cover of one of the cylinders with the valve cover 8, with the camshaft position sensor installed in it, connect the connecting wires, turn on the electronic information collection unit. Then, the engine power control controller is set to the target position, for example, the 8th out of 16 possible, and it is expected that the engine parameters will stabilize at the set speed and stabilize the power level at the rheostat installation in the rheostat test mode (rheostat is a tank with water and contact plates, designed for utilization of electric energy generated by a diesel-generator set of a locomotive, the electric motors of the wheel drives are disconnected from the power supply). It is also possible to load the brake resistors built into the locomotive, taking into account the correspondence of the power generated by the engine. It is also possible to carry out diagnostics while driving, provided the road is evenly spaced, on which it is possible to provide the desired operating mode of the diesel generator set. After achieving a stable operating mode at the desired position of the controller of the locomotive driver, a request is made for data from the information collection unit. The information collection unit accumulates an array of data for one engine operation cycle (2 crankshaft revolutions for a 4-stroke engine) and transfers it to the computer for analysis.

After that, the device can be reused, or for the diagnosis of other engines of diesel engines of this type.

Thus, due to the mechanically fixed reference mark of the proposed design, the availability of technical means for the operation of the device, this device can be widely used in the field of railway transport for the diagnosis of a 16-cylinder diesel engine, both during stops of the diesel locomotive and during the movement of the diesel locomotive ( subject to the uniformity of load on a certain section of the road).

Claims (1)

A device for diagnosing an internal combustion engine, comprising a sensor for measuring a speed of movement of a flywheel installed in a window of a flywheel housing and an engine camshaft position sensor associated with an electronic data collection unit, characterized in that the camshaft position sensor is located in a valve cover of one of the cylinders of the internal engine combustion.

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